Compact InAs Quantum Dot Multilayers Realizing High-Power Lasers

Utilizing quantum dots as gain medium to achieve ultra-high optical output at telecommunication wavelength remains a persistent goal. In this work, we present an approach to enhance optical gain while maintaining a compact active region, suitable for high-power quantum dot lasers operating at wavelength of 1.31 μm. By reducing the growth temperature of InAs quantum dot (QD) in the latter layers, compact 12-layer QDs with high density and photoluminescence intensity are achieved. Based on this optimized structure, high-power QD lasers are grown and fabricated with 1600 μm cavity length and 2.5 μm ridge width, delivering a maximum output power of 212 mW, a peak wall-plug efficiency of 16%, and a maximum net modal gain of 6.6 cm^-1 at room-temperature (RT). Moreover, the device demonstrates excellent thermal robustness, maintaining 99 mW output power at 110 ℃.